How shemales are made?

They are born boys and later in life they become trans women. They are not a gender of their own. Wiki:

Shemale is a term used in sex work to describe trans women with male genitalia and augmented female breasts from breast augmentation and/or use of hormones. Using the term she-male for a transsexual woman would be considered highly offensive, for it implies that she is working in the sex trade.